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<meta charset="utf-8">
<title>菜鸟教程(runoob.com)</title>
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<p> typeof 操作符返回变量或表达式的类型。</p>
<p id="demo"></p>
<script>
document.getElementById("demo").innerHTML = 
	typeof "john" + "<br>" + 
	typeof 3.14 + "<br>" +
	typeof false + "<br>" +
	typeof [1,2,3,4] + "<br>" +
	typeof {name:'john', age:34};
</script>

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